Role of the phospholipase c and tyrosine kinase systems in the growth response of human airway smooth muscle cells. De, S., E. T. Zelazny, J. F. Souhrada, and M. Souhrada. The John B. Pierce Laboratory and Yale University School of Medicine
APStracts 2:0230L, 1995.
The primary culture of confluent human ASM cells were exposed up to five days to human recombinant IL-1b in the presence of indomethacin and 1% fetal bovine serum. The proliferation was assessed by a [3H] -thymidine incorporation and direct cell count. We found that IL-1b significantly increased thymidine incorporation and cell count into ASM cells in a concentration-dependent manner. Pretreatment of cells with specific polyclonal antibodies against platelet-derived growth factor (PDGF-BB homodimer) completely inhibited the IL-1b-induced increase in thymidine incorporation. The PDGF-BB, at the concentrations of 1.5 and 2.5 ng/ml, stimulated the proliferation of ASM cells. The proliferative action of IL-1b was potentiated when PDGF-BB was added into the medium in combination with IL-1b. Pretreatment of cells with genistein (0.37 M), a specific tyrosine kinase inhibitor, attenuated the proliferative effect of IL-1b and PDGF-BB.

Received 10 May 1995; accepted in final form 7 December 1995.
APS Manuscript Number L144-5.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 23 December 95